Compiled by Photonics Spectra staff
RALEIGH, N.C. – Fiber optic network designers must find the most efficient way to connect
distant phones and computers – a costly and time-consuming process. But researchers
at North Carolina State University have a model that they say finds optimal connections
10,000 times more quickly than previously possible, while using less computer power
to solve the problem.
“Problems that used to take days to solve can now be solved
in just a few seconds,” said George Rouskas, a computer science professor
at the university. The model could solve problems much faster when data is routed
through larger “rings” in the network, he said.
Devising a mathematical model, the researchers identified the
exact optimal routes and wavelengths for ring network designers. The model creates
a large graph of all the paths in a ring and identifies where those paths overlap.
It then breaks the graph into smaller units, with each unit consisting of the paths
that do not overlap. Because they don’t overlap, they can use the same wavelength
of light, whereas paths that overlap cannot.
By breaking all of the potential paths down into smaller groups,
the scientists identified the optimal path and wavelength between two points much
more efficiently than they could using previous techniques. Their work appeared
in the July issue of the Journal of Optical Communications and Networking (doi:
The researchers say the model will significantly shorten the cycle
of feed-back and redesign for existing rings, meaning that the ring design work
could be done using fewer computers, costing less. In addition, it should allow network providers to be more responsive to user demands than previous models permitted.